The best replacement for cortana is edi.

The best alternatives to cortana are rated as following:
★★★★★  edi
★★★★  siri
★★★★  kinvara
★★★  jarvis
★★  jane
★★  glados
★  halo 4 cortana
★  shodan
  google now
  master chief

Your alternative for cortana is not listed? Suggest!
Speaking about cortana, one probably shouldn't forget about master chief.

Other search terms related to cortana and their ratings are:
★★★★★ master chief
You have in mind a companion for cortana and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of cortana in all years. Click on graph for more.
cortana
edi
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